201134091 六、發明說明： 【發明所屬之技術領域】 本發明有關於調譜（_)具有内嵌天線之射頻（radi〇_frequency， RF)前端（front-end)電路’且特別有關於一種藉由使用晶載（〇n chip) 負跨導（trans-conductance)電路調諧射頻前端電路至期望之射頻頻寬 以形成振盪器之方法、射頻前端電路以及濾波校正系統。 【先前技術】 射頻接收器被廣泛應用於電視、蜂巢電話、尋呼器、全球定位系 統（global positioning system，GPS)接收器、有線調變解調器、無線 電話、接收射頻訊號之無線電與其他設備。舉例而言，在美國，對於 調頻（frequency modulate ’以下簡稱為FM)音訊廣播，⑽音訊訊號 廣播於頻率76 MHz至l〇8MHz的頻寬中。 於傳統接收地面（terrestrial)音訊廣播之系統中，通常使用濾波 .電路以濾除經由天線接收之訊號頻譜中之不需要之部分。因此，上述 濾'波電路（至少-部分），將輸入訊號調諸至期望之通道或射頻訊號頻 譜之一部分。舉例而言，對於FM地面音訊廣播，上述攄波電路可幫 助將接收器調諧至期望之FM通道。 FM接收器通常使用耳機線（headph〇ne wires)作為主要的長天 線。其存在的問題為，於耳機與接收H斷開連接後，就沒有訊號接收。 因此，在用戶需要具有内嵌天線的接收器，其中内嵌天線應提供用 4 201134091 -於接收FM訊號的支援。 類似地於某二應用中，用戶需要可從數位圖書館（出娜丨出㈣） 設備得到音細_ FM較讀送之發送料路，舉綱言，以 於駕驶時於車載無線電上播放。上述FM發送器亦使肋嵌天線用於 發送。 第圖為幵y成於印製電路板（printed咖此，以下簡稱為 )10上之内礙天線12之示意圖。内嵌天線12可通過多種不同方 式=成’例如其下沒有接地層（gr_d la㈣之pcB走線〇職）。 内瓜天線12亦可由纏饒於諸如行動電話之設備之外殼之簡單饒線 (We)形成。内嵌天線12用作FM與其他廣播應用之天線。内嵌天 線12 ’其長度遠小於透過内嵌天線^接收之訊號之訊號波長（〜 length) ’其等效電路模型僅為電容器，這裡稱之為％。舉例而言， 内嵌天線12之等效電容器CANT之範圍可為l-l〇PF。 相較於用於FM接收之傳統長天線而言，内嵌天線u之接收低數 十dB。為了提高天線輸出端之訊號等級，可使用分流電感器與内嵌天 線12之專效電谷譜振（比⑽仙腦）以形成高諧振（高q)，從而獲得 電壓增益。’收頻寬所期望之頻寬寬度通常為寬頻，必須調譜為槽 (tank)譜振頻率。於先前技術中，係使用可調諸晶載電容器 陣列， 里由開關並聯之多個電容器分支，以轉換諧振頻率。然而，先前 技術中仍存在問題，即如何自動並精確地測量槽的諳振頻率以將其調 諧至適當數值。 201134091 因此’需要一種改進的調諧内嵌天線系統之方法。 【發明内容】 有鑑於此，特提供以下技術方案： 本發明實施例提供—種射頻前端電路，包含··可調諧滤波器；負 跨導電路，搞接於可調譜濾波器，以產生調譜振盤訊號；計數器，用 於疋調諧紐峨之鮮；以及控制電路，驗藉由酿可調措滤 波器以移動鱗紐觸^鮮，直到調雜盪域之頻轉於可接 受之頻率範_，射可接受之鮮細對應於·之通道頻帶。 八本發明實施则提供—_於射㈣端電路之驗校正系統，包 含：可觸舰n，用於射調整觸控舰賴繼至之通道， 其中可調韻波H可橫跨包含多個通道之鮮頻譜而瓣；負跨導 :制=於:職波器，以於校正模式中產生調諧振盪訊號;以及 工’祕接絲_諧缝峨之_峨，從㈣由調整 調諧濾波《以軸繼縫訊狀_ 9 0 r接受之__，其中可接受之頻率：：:= 本發明實施例另提供-種調諧射頻前端電 耦接於可毅H之貞料，產 1 ’ &含：利用 盪訊號之_ .以及m/顧峨；決定調譜振 革及藉_整可樹錢如軸购振盪訊號之頻 6 201134091 以上所述之射頻前端電路 之方法，藉由使用回饋迴路， 率。 、濾波校正系統以及調諧射頻前端電路 可快速、自動地調諧射頻前端電路之頻 .實施方式】 —於·書及錢的申請專利範圍當巾制了某侧彙來指稱特 的讀。所屬領域中具有通常知識者應可理解，硬體製造商可能會用 不同的名詞來稱呼_的元件。本說明書及後續的申請專利範圍並不 以名稱的差異來作為區分元件的方式，岐以元件在魏上的差異來 作為區分的準則。於通篇說明書及後續的請求項當中所提及的「包含」 係為-開放式的用語，故應解釋成「包含但不限定於」。另外，「輕接」 -詞在此係包含任何直接及間接的魏連接手段n若文中描述」 :第-裝置鵪接於-第二裝置，則代表該第—裝置可直接電氣連接於 该第二裝置，或透過其他裝置或連接手段間接地電氣連接至該第二裝 置。 本發明提供一種具有增強的調諧方法之射頻前端電路。第2圖為 射頻前端電路100之功能方塊圖。射頻前端電路100包含可調諧濾波 器102，其由控制電路112輸出之調諧控制訊號〗24控制。負跨導電 路104連接至可調譜滤波器1〇2。諧振時，負跨導電路之負跨導 抵銷射頻前端電路100中之其他元件之槽損失，以維持振盪並產生調 201134091 諳振盪訊號122。 δ十數器110測量調諧振盪訊號122之振盪頻率以計算一計數值。 於調諧程序期間，於-個計數週期期間，計數器11〇對調諧振蘯訊號 122接收之脈波的數量計數，以計算上述計數值。同時，於晶載精密 時脈的協助下’控制電路112計算射頻前端電路1〇〇被適當地調譜至 正確頻率，即期望之通道頻帶時，調諧振盪訊號122於計數週期内之 麵之脈波數i。織，計數n 11G料數錄&至_電路112， 以讓控制電路112料數值無期之職數量比較。若從計數器11〇 接收之計數值足夠接近控制電路112計算之預期之值，或於預定範圍 内’則認為射頻前端電路1〇〇被適當地調諧。若計數值不處於預期之 值之預定細内’雌㈣路112改魏馳觀號124之值以調整 可調謂渡波器102 ’從而調整調譜振盪訊號122之振盪頻率。一旦調 諧振遭訊號122之振盪頻率處於期望之通道頻帶之可接受之範圍内， 控制電路m鎖存Oatch)調譜控制訊號m之期望值，然後負跨導 電路104被銳以餘普通模式操作。負跨導· 1()4產生用於^整 或調諧射頻前端電路1〇〇之頻率之調譜振盈訊號122。計數器⑽對 調譜振魏號122之減_計數並將上料數健供至控制電路 U2作為回饋。使用可調諧渡波器1〇2、負跨導電路ι〇4、計數器則、 以及控制電路112構成之回饋迴路，射步驗端電路卿之頻率可被快 速、準確、以及自動地調諧。 、 第3圖為藉由第2圖中所示之射頻^^端電路1〇〇執行之頻率調諧 8 201134091 ;:Γ150中’為射頻前端電路1〇。選擇期望之綱 :波:諧:_122利用負跨導電_與可調 調麵訊號122之頻率計數後二步:154中，藉由計數器110對 料冲數然後’於步驟156中，控制電路112 決定調諧滅峨122之_是錢_ 範圍内。若是，職行步驟⑽鮮之可接受頻率 則執仃步驟158。於步驟158 112利用調譜控制訊號_整可調_器1〇2以轉 換繼缝訊號122之頻率。上述調譜方法於步驟160中結束。 第圖為根據本發明一實施例之射頻收發器前端電路彻之詳細 龙圖。第5圖為模擬部分射頻收發器前端電路及其對產生之增 =之振細率之影響之等效電路圖。分流電感器郷與所有連接至 /頻皐之電#之和雜，且產生之諧振頻率等於期望之通道頻帶。可 “白電合電路308可被控制以針對不同的期望射頻通道調譜（轉 上述諧振頻率。 、 於第4圖所示之實施例中，第4圖之負跨導電路3〇4對應於第2 圖之負跨導電路UM，第4圖之分流電感器篇與可調諧電容電路3〇8 對應於第2圖之可調譜滤波器1〇2，第4圖之數位計數器則對應於 第2圖之计數器110，以及第4圖之數位訊號處理器（DSpm2對應 於第2圖之控制電路112。 々内嵌天線302用於發送或接收射頻訊號，且内嵌天線3〇2可模擬 A文電阻RANT與荨效電容匸丽之串接。射頻收發器前端電路3〇〇 201134091 可用於支援射頻訊號之接收與發送，其中射頻訊號處於76 MHz至108 MHz之調頻廣播頻帶。 射頻收發器前端電路300滿足下述目標將十分受歡迎，即自動將201134091 VI. Description of the Invention: [Technical Field of the Invention] The present invention relates to a radio frequency (RF) front-end circuit having an embedded antenna, and particularly relates to a borrowing A method, an RF front end circuit, and a filter correction system for tuning an RF front end circuit to a desired RF bandwidth using a 〇n chip negative trans-conductance circuit to form an oscillator. [Prior Art] RF receivers are widely used in televisions, cellular phones, pagers, global positioning system (GPS) receivers, cable modems, wireless phones, radios that receive RF signals, and others. device. For example, in the United States, for frequency modulate (hereinafter referred to as FM) audio broadcasting, (10) audio signals are broadcast in a frequency range of 76 MHz to 10 〇 8 MHz. In conventional terrestrial audio broadcast systems, a filtering circuit is typically used to filter out unwanted portions of the signal spectrum received via the antenna. Therefore, the filter circuit (at least - part) filters the input signal to a desired portion of the channel or RF signal spectrum. For example, for FM terrestrial audio broadcasting, the chopper circuit described above can help tune the receiver to the desired FM channel. FM receivers typically use headphone lines as the primary long antenna. The problem is that after the earphone is disconnected from the receiving H, there is no signal reception. Therefore, the user needs a receiver with an embedded antenna, and the embedded antenna should provide support for receiving FM signals with 4 201134091. Similarly, in a second application, the user needs to obtain a sound _ FM from the digital library (the fourth out of the four (4)) equipment to send the material path, to outline, in order to play on the car radio while driving. The FM transmitter described above also allows the ribbed antenna to be used for transmission. The figure is a schematic diagram of the antenna 12 in the printed circuit board (hereinafter referred to as "the printed circuit board"). The embedded antenna 12 can be implemented in a number of different ways = for example, there is no ground layer under it (gr_d la (four) pcB routing). The melon antenna 12 can also be formed by a simple wire (We) wrapped around the outer casing of a device such as a mobile phone. The embedded antenna 12 is used as an antenna for FM and other broadcast applications. The embedded antenna 12' has a length much smaller than the signal wavelength (~length) of the signal received through the embedded antenna^. The equivalent circuit model is only a capacitor, which is referred to herein as %. For example, the equivalent capacitor CANT of the embedded antenna 12 may have a range of l-l〇PF. The reception of the embedded antenna u is tens of dB lower than that of the conventional long antenna for FM reception. In order to increase the signal level at the output of the antenna, a shunt inductor and a dedicated electric valley spectrum (in contrast to (10) Xiannao) of the embedded antenna 12 can be used to form a high resonance (high q) to obtain a voltage gain. The desired bandwidth width is usually broadband and must be tuned to the tank spectral frequency. In the prior art, an array of crystal-loaded capacitors is used in which a plurality of capacitor branches in parallel are switched in parallel to convert the resonant frequency. However, there is still a problem in the prior art, namely how to automatically and accurately measure the frequency of the oscillation of the groove to tune it to an appropriate value. 201134091 Therefore, there is a need for an improved method of tuning an in-line antenna system. SUMMARY OF THE INVENTION In view of this, the following technical solutions are provided: The embodiment of the present invention provides a radio frequency front-end circuit, including a tunable filter, and a negative transconductance circuit, which is connected to a tunable spectral filter to generate a tone. Spectral disk signal; counter, used to tune the neon of the neon; and the control circuit, the filter is adjusted by the filter to move the scale, until the frequency of the tune domain is switched to an acceptable frequency. Fan _, the acceptable thickness of the shot corresponds to the channel band of . The eight inventions provide an inspection-correction system for the (four)-end circuit, including: a tactile ship n, which is used to adjust the channel of the touch ship Lai Jizhi, wherein the adjustable rhyme H can span multiple The fresh spectrum of the channel and the flap; negative transconductance: system = in: the wave machine, in order to generate the tuning oscillation signal in the calibration mode; and the work 'secret wire _ 峨 峨 峨 峨 从 从 峨 峨 峨 峨 峨 峨 调整 调整 调整 调整 调整 调整Accepted by the axis splicing _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Including: using the slogan _ and m/Gu 峨; deciding to adjust the spectrum and borrowing _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Loop, rate. The filter correction system and the tuned RF front-end circuit can quickly and automatically tune the frequency of the RF front-end circuit. The implementation method] - The patent application scope of the book and the money is used to form a certain side to refer to the special reading. Those of ordinary skill in the art should understand that hardware manufacturers may use different nouns to refer to the elements of _. The scope of this specification and the subsequent patent application do not use the difference in name as the means of distinguishing the elements, and the difference in the elements is used as the criterion for distinguishing. The term "including" as used throughout the specification and subsequent claims is an open-ended term and should be interpreted as "including but not limited to". In addition, the term "light" - the term "includes any direct and indirect connection means" as described in the text: "the device-connected to the second device" means that the device can be directly electrically connected to the first device. The second device is electrically connected to the second device indirectly through other devices or connection means. The present invention provides a radio frequency front end circuit with an enhanced tuning method. Figure 2 is a functional block diagram of the RF front end circuit 100. The RF front end circuit 100 includes a tunable filter 102 that is controlled by a tuning control signal 24 output by the control circuit 112. The negative transconductance path 104 is connected to the tunable spectral filter 1〇2. During resonance, the negative transconductance of the negative transconductance circuit cancels the slot loss of other components in the RF front end circuit 100 to maintain oscillation and produce a modulated 201134091 谙 oscillation signal 122. The delta sigma 110 measures the oscillating frequency of the tuned oscillating signal 122 to calculate a count value. During the tuning process, during a counting period, the counter 11 〇 counts the number of pulse waves received by the resonant chirp signal 122 to calculate the above count value. At the same time, with the help of the crystal-loaded precision clock, the control circuit 112 calculates that the RF front-end circuit 1 is properly tuned to the correct frequency, that is, the desired channel frequency band, and modulates the surface of the oscillation signal 122 during the counting period. Wave number i. Weaving, counting n 11G material count & to _ circuit 112, in order to let the control circuit 112 count the number of unscheduled jobs. The RF front end circuit 1 is considered to be properly tuned if the count value received from the counter 11A is sufficiently close to the expected value calculated by the control circuit 112, or within a predetermined range. If the count value is not within the predetermined fineness of the expected value, the female (four) way 112 changes the value of the Weichi view 124 to adjust the adjustable wave former 102' to adjust the oscillation frequency of the modulated oscillation signal 122. Once the oscillating frequency of the modulated resonant signal 122 is within an acceptable range of the desired channel band, the control circuit m latches the Oatch) desired value of the modulating control signal m, and then the negative transconductance circuit 104 is operated in the normal mode. The negative transconductance 1()4 generates a spectral excitation signal 122 for tuning or tuning the frequency of the RF front end circuit 1〇〇. The counter (10) subtracts the count _ of the modulo vibration number 122 and supplies the number of feeds to the control circuit U2 as feedback. Using the tunable waver 〇2, the negative transconductance circuit ι4, the counter, and the feedback loop formed by the control circuit 112, the frequency of the pedestal circuit can be tuned quickly, accurately, and automatically. Figure 3 is a frequency tuning 8 201134091 performed by the RF terminal circuit 1 shown in Fig. 2; Γ150 is the RF front-end circuit 1〇. Selecting the desired line: Wave: Harmonic: _122 uses the negative span conduction _ and the frequency of the adjustable surface signal 122 to count after two steps: 154, the counter is counted by the counter 110 and then 'in step 156, the control circuit 112 determines The tuning 峨 122 is in the range of money _. If yes, step (158) is performed at step (10). At step 158 112, the frequency of the relay signal 122 is converted by the tone control signal _ adjuster _1. The above method of phasing ends in step 160. The figure is a detailed diagram of a front end of a radio frequency transceiver according to an embodiment of the invention. Figure 5 is an equivalent circuit diagram simulating the front-end circuit of a part of the RF transceiver and its effect on the resulting increase in the vibrating rate. The shunt inductor 郷 is summed with all the power connected to / 皋, and the resulting resonant frequency is equal to the desired channel frequency band. The white-lighting circuit 308 can be controlled to modulate the spectrum for different desired RF channels (toward the resonant frequency described above. In the embodiment illustrated in FIG. 4, the negative transconductance circuit 3 〇 4 of FIG. 4 corresponds to The negative transconductance circuit UM of Fig. 2, the shunt inductor section of Fig. 4 and the tunable capacitance circuit 3〇8 correspond to the tunable spectral filter 1〇2 of Fig. 2, and the digital counter of Fig. 4 corresponds to The counter 110 of FIG. 2 and the digital signal processor of FIG. 4 (DSpm2 corresponds to the control circuit 112 of FIG. 2. The built-in antenna 302 is used for transmitting or receiving an RF signal, and the embedded antenna 3〇2 The A-resistor RANT can be simulated in series with the effective capacitor. The RF transceiver front-end circuit 3〇〇201134091 can be used to support the reception and transmission of RF signals, where the RF signal is in the FM broadcast band from 76 MHz to 108 MHz. The transceiver front-end circuit 300 will be very popular to meet the following objectives, that is, automatically
内嵌天線302調s皆至76 MHz至108 MHz之頻帶内之期望之FM 通道。藉由射頻收發器前端電路300提供之調諧靈活性（flexibility) 亦允許使用多種内嵌天線配置，使得上述電路可用於多種不同的產品 中。 於一實施例中，積體電路325用於整合射頻收發器前端電路3〇〇 之數個元件。於下文之描述中，“晶載”元件位於積體電路325之上， 而“晶外，，元件不位於積體電路325之上。舉例而言，於一實施例中， 所有晶外元件與積體電路325，皆排佈於1»(：33〇5上，且pCB具有其 自身的等效電容CPCB。 於一實施例中’分流電感器306位於晶外，並用於與内嵌天線3〇2 之電容Cant諧振。分流電感器306以等效電感^實現。可調諸電容 電路308為可變晶載電容電路，依據應用可為離散的或連續的，並且 由a曰載DSP 312輸出之調譜控制訊號324控制。可調譜電容電路3〇8 以等效電感E CVAR實現。晶載負跨導電路3〇4用於提供負跨導以及與 諧振槽振盪。負跨導電路304被模擬為等效電阻^與等效電容c柳 之並接。於祕時，負跨導電路3〇4之負跨導抵銷射頻收發器前端電 路300中之其他元件之槽損失，以維持錄並產生調譜振蓋訊號功。 201134091 於—實施例中，可調諧電容電路遍包含電容器陣列，且可係為 晶載或晶外元件。可調譜電容電路期之電容值可為離散的或連續 的’以及可調諧電容電路迎由調諧控制訊號324控制，而此控制可 為數位式、類比式、或數位與類比混合式。 於-實施财，可_電容電路·為可綱電容_，以及可 調諧電容電路與分流電感_皆連接於使用分流配置之訊號路 控。曰於另一實施例中，如第5圖所示，内嵌天線3〇2與分流電感器3〇6 係晶外7L件’而負跨導電路與可調諧電容電路篇係晶載元件。 於校正模式期間，負跨導電路304被致能，以及數位計數器則 參考一參考時脈CLKref以測量調譜缝訊號322之減頻率。參考時 脈CI^Kref大致上為恒定時脈頻率，可用作對其他訊號計數之參考。舉 例而。參考時脈CLKref可為晶體產生之％ MHz時脈。數位計數器 一”參考夺脈CLKref皆可整合為晶載元件。於參考時脈clk^指 示之^週期内，數位計數器31〇藉由對_振盈訊號322之脈波計 數來計算計數值，以協助調諧程序。 ;於私知序期間’於一個計數週期0，數位計數器則對調譜振 盧冰號_ 2之接收的脈波數量計數，以計算計數值。同時，DSP 312 计算t振盪峨322之預期之脈波數量，此預期之脈波數量係射頻 收發器前端電路3〇(H皮適當地調諧至正確頻率時，於計數週期内應當 接收之數量。然後’數位計數器31〇將計數值輸出至膽312，以讓 DSP 312將推值與預期之脈波數量比較。若從數位計數器⑽接收 201134091 之計數值足夠接近DSP 312計算之預期之值，或處於預定範圍内，則 認為射頻收發器前端電路300被適當地調諧。若計數值未處於預期之 值之預定範圍内，則DSP 312改變調諧控制訊號324之值以調整可調 諧電容電路308之可變電容CVAR，從而調整調諧振盪訊號322之振盪 頻率。一旦調諧振盪訊號322之振盪頻率處於可接受之範圍内，Dsp 312鎖存調諧控制訊號324之所需值，然後負跨導電路3〇4被禁能以 用於普通模式操作。因此’使用上述調諸方法，負跨導電路304產生 用於調整或調諧射頻收發器前端電路300之頻率之調諧振盈訊號 322。數位計數器310對調諧振蘯訊號322之振蘯頻率計數並將上述計 數值提供至DSP 312作為回饋。使用回饋迴路，射頻收發器前端電路 300之頻率可被快速、自動地調諧。 請繼續參考第4圖。射頻收發器前端電路3〇〇具有發送射頻訊號 與接收射頻訊號之功能。對於接收射頻訊號，晶載低雜訊放大器（以 下簡稱為LNA)314用於放大透過内嵌天線302接收之接收射頻訊號， 以產生放大之接收射頻訊號。晶載接收混頻器316用於對放大之接收 射頻訊號進行頻率下轉換以用於後續處理。LNA 314之輸入阻抗可模 擬為等效電阻RLNA與等效電容Clna之並接。 對於發送射頻訊號，晶載功率放大器（以下簡稱為PA) 318用於 放大將發送之射頻訊號，以產生透過内嵌天線302發送之放大之發送 射頻訊號。PA 318可實現為等效電容CPA與等效電阻RPA及等效電流 源IpA之並接。 12 201134091 第6圖為射頻接收器前端電路400之方塊圖。與第4圖中所示之 射頻收發斋前端電路3〇〇不同’射頻接收器前端電路4〇〇僅接收射頻 讯號但不包含發送器功能。因此，用於發送射頻訊號之pA318未包含 於射頻接收器前端電路4〇〇中。對於射頻接收器前端電路4〇〇中之所 有其他兀件’其功能與上文對於射頻收發器前端電路雙之描述相同。 第7圖為射頻發送器前端電路5〇〇之方塊圖。與第4圖中所示之 射頻^1欠發益刖端電路3〇〇不同，射頻發送器前端電路5〇〇僅發送射頻 心虎但不包含接收器功能。因此，用於接收射頻訊^lna314與混 頻器316未包含於射頻發送器前端電路5〇〇 +。對於射頻發送器前端 電路500中之所有其他兀件，其魏與上文對於射頻收發$前端電路 300之描述相同。 射頻收發器前端電路300、射頻接收器前端電路4〇〇、以及射頻發 送器前端電路500 +分適合接收或發送FM無線電訊號。内嵌天線搬 ，長度可小於X/4，甚至更小於跡其中波長χ與用於發送或接收訊 唬之射頻前端電路所需之調諧頻率有關。 本發明提出之觸方法除簡單之外，使用本發明提出之解決方案 之另-主要優勢為’用於接收H或發送器之觸演算法與用於產生本 地振堡器之合成器（synthesizer)中使用之晶載電麼控制振蘆器（以下 簡稱為VCO)之觸方法十分類似。因此，vc〇與内嵌天線調猎可 重用同一數位硬體。這樣，就無需額外數位硬體。 201134091 以上所述僅為本發明之較佳實施例，舉凡熟悉本案之人士援依本 發明之精神所做之㈣變化與修飾，㈣涵蓋於_之申料利範圍 内0 【圖式簡單說明】 第1圖為形成於PCB上之内嵌天線之示意圖。 第2圖為射頻前端電路之功能方塊圖。 第3圖為藉由第2圖中所示射頻前端電路執行之頻率調諧方法之 流程圖。 第4圖為射頻收發器前端電路之詳細方塊圖。 第5圖為模擬部分射頻收發器前端電路以及其對產生之諧振槽之 振盪頻率之影響之等效電路圖。 第6圖為射頻接收器前端電路之方塊圖。 第7圖為射頻發送器前端電路之方塊圖。 【主要元件符號說明】 10'305 ： PCB ； 100 :射頻前端電路； 104'304 :負跨導電路； 112 :控制電路； 124、324 :調諧控制訊號； 300 :射頻收發器前端電路； 308 :可調諧電容電路； 12、302 :内嵌天線； 102 :可調諧濾波器； 110 :計數器； 122、322 :調諧振盪訊號； 150〜160 :步驟； 306 :分流電感器； 310 :數位計數器； 201134091 314 ： LNA ； 312 ： DSP ； 316 :混頻器； 318 : PA ; 325 :積體電路； 400 :射頻接收器前端電路； 500 :射頻發送器前端電路。The embedded antenna 302 adjusts to the desired FM channel in the band of 76 MHz to 108 MHz. The flexibility provided by the RF transceiver front end circuit 300 also allows for the use of a variety of embedded antenna configurations, making the above circuits available in a variety of different products. In one embodiment, the integrated circuit 325 is used to integrate the components of the RF transceiver front end circuit 3〇〇. In the following description, the "on-chip" component is located above the integrated circuit 325, and "outside, the component is not located above the integrated circuit 325. For example, in one embodiment, all of the extra-crystalline components are The integrated circuit 325 is arranged on 1»(:33〇5, and the pCB has its own equivalent capacitance CPCB. In one embodiment, the shunt inductor 306 is located outside the crystal and is used with the embedded antenna 3 The capacitor Cant resonates with 〇 2. The shunt inductor 306 is implemented with an equivalent inductance. The tunable capacitor circuit 308 is a variable crystal-load capacitor circuit that can be discrete or continuous depending on the application and output by the DSP 312. The modulating control signal 324 is controlled. The tunable spectral capacitor circuit 3 〇 8 is implemented with an equivalent inductance E CVAR. The crystal carrying negative transconductance circuit 3 〇 4 is used to provide a negative transconductance and oscillate with the resonant tank. Negative transconductance circuit 304 It is simulated as the equivalent resistance ^ and the equivalent capacitance c will be connected. At the secret time, the negative transconductance of the negative transconductance circuit 3〇4 offsets the slot loss of other components in the RF transceiver front-end circuit 300 to maintain Record and generate the modulating and oscillating signal function. 201134091 In the embodiment, tunable The capacitor circuit includes a capacitor array and may be a crystal carrier or an extra-crystalline component. The capacitance value of the tunable spectral capacitor circuit may be discrete or continuous 'and the tunable capacitor circuit is controlled by the tuning control signal 324, and this The control can be digital, analog, or analog-to-analog hybrid. In the implementation, the _capacitor circuit is a capacitor _, and the tunable capacitor circuit and the shunt inductor _ are connected to the signal path using the shunt configuration. In another embodiment, as shown in FIG. 5, the embedded antenna 3〇2 and the shunt inductor 3〇6 are externally connected to the 7L piece', and the negative transconductance circuit and the tunable capacitor circuit are systematically loaded. During the correction mode, the negative transconductance circuit 304 is enabled, and the digital counter refers to a reference clock CLKref to measure the decrement frequency of the modulating slit signal 322. The reference clock CI^Kref is substantially constant clock frequency. It can be used as a reference for counting other signals. For example, the reference clock CLKref can be the % MHz clock generated by the crystal. The digital counter can be integrated into the crystal carrier component by reference to the pulse CLKref. During the period, the digital counter 31 calculates the count value by counting the pulse wave of the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ The number of pulses received by the icicle _ 2 is counted to calculate the count value. At the same time, the DSP 312 calculates the expected number of pulses of the t-oscillation 322, which is the number of pulses of the RF transceiver front-end circuit 3 The number that should be received during the counting period when properly tuned to the correct frequency. The 'counter counter 31' then outputs the count value to the chord 312 to allow the DSP 312 to compare the push value to the expected number of pulses. (10) The RF transceiver front end circuit 300 is considered to be properly tuned to receive the 2011 34091 count value sufficiently close to the expected value calculated by the DSP 312, or within a predetermined range. If the count value is not within the predetermined range of the expected value, the DSP 312 changes the value of the tuning control signal 324 to adjust the variable capacitance CVAR of the tunable capacitance circuit 308 to adjust the oscillating frequency of the tuned oscillating signal 322. Once the oscillating frequency of the tuned oscillating signal 322 is within an acceptable range, the Dsp 312 latches the desired value of the tuning control signal 324, and then the negative transconductance circuit 3 〇 4 is disabled for normal mode operation. Thus, using the above described method, the negative transconductance circuit 304 produces a modulated resonant signal 322 for adjusting or tuning the frequency of the RF transceiver front end circuit 300. The digital counter 310 counts the vibrating frequency of the resonant chirp signal 322 and provides the above count value to the DSP 312 for feedback. Using the feedback loop, the frequency of the RF transceiver front end circuit 300 can be quickly and automatically tuned. Please continue to refer to Figure 4. The RF transceiver front-end circuit 3 has the function of transmitting an RF signal and receiving an RF signal. For receiving the RF signal, a crystal carrier low noise amplifier (hereinafter referred to as LNA) 314 is used to amplify the received RF signal received through the embedded antenna 302 to generate an amplified received RF signal. The crystal-carrying receive mixer 316 is for frequency down-converting the amplified received RF signal for subsequent processing. The input impedance of the LNA 314 can be modeled as the parallel connection of the equivalent resistance RLNA and the equivalent capacitance Clna. For transmitting RF signals, a crystal-loaded power amplifier (hereinafter abbreviated as PA) 318 is used to amplify the RF signals to be transmitted to generate amplified RF signals transmitted through the embedded antenna 302. The PA 318 can be implemented as a parallel connection of the equivalent capacitor CPA and the equivalent resistor RPA and the equivalent current source IpA. 12 201134091 Figure 6 is a block diagram of the RF receiver front end circuit 400. Unlike the RF transceiver front-end circuit shown in Figure 4, the RF receiver front-end circuit 4 receives only the RF signal but does not include the transmitter function. Therefore, the pA318 for transmitting the RF signal is not included in the RF receiver front-end circuit 4A. All of the other components in the RF Receiver Front End Circuit 4' have the same function as described above for the RF Transceiver Front End Circuit. Figure 7 is a block diagram of the RF transmitter front-end circuit 5〇〇. Unlike the RF^1 发 刖 terminal circuit 3〇〇 shown in Figure 4, the RF transmitter front-end circuit 5〇〇 transmits only the RF heartbeat but does not include the receiver function. Therefore, the receiving RF signal 314 and the mixer 316 are not included in the RF transmitter front end circuit 5 〇〇 +. For all other components in the RF Transmitter Front End Circuit 500, it is the same as described above for the RF Transceiver $ Front End Circuit 300. The RF transceiver front end circuit 300, the RF receiver front end circuit 4, and the RF transmitter front end circuit 500+ are adapted to receive or transmit FM radio signals. The embedded antenna can be less than X/4, or even smaller than the wavelength of the trace, which is related to the tuning frequency required for the RF front-end circuitry used to transmit or receive the signal. In addition to being simple, the touch method proposed by the present invention has the additional advantage of using the solution proposed by the present invention as 'a touch algorithm for receiving H or a transmitter and a synthesizer for generating a local vibrator. The touch method used to control the vibrator (hereinafter referred to as VCO) is very similar. Therefore, vc〇 and embedded antenna hunting can reuse the same digital hardware. This way, no extra digital hardware is needed. 201134091 The above is only a preferred embodiment of the present invention, and those who are familiar with the present invention will make (4) changes and modifications according to the spirit of the present invention, and (4) cover the scope of the application within the scope of _ [Simple Description] Figure 1 is a schematic diagram of an embedded antenna formed on a PCB. Figure 2 is a functional block diagram of the RF front-end circuit. Figure 3 is a flow chart of the frequency tuning method performed by the RF front end circuit shown in Figure 2. Figure 4 is a detailed block diagram of the RF transceiver front-end circuit. Figure 5 is an equivalent circuit diagram of the analog RF transceiver front-end circuit and its effect on the oscillation frequency of the resulting resonant tank. Figure 6 is a block diagram of the RF receiver front-end circuit. Figure 7 is a block diagram of the RF transmitter front-end circuit. [Main component symbol description] 10'305: PCB; 100: RF front-end circuit; 104'304: Negative transconductance circuit; 112: Control circuit; 124, 324: Tuning control signal; 300: RF transceiver front-end circuit; Tunable Capacitor Circuit; 12, 302: In-line Antenna; 102: Tunable Filter; 110: Counter; 122, 322: Tuned Oscillation Signal; 150~160: Step; 306: Shunt Inductor; 310: Digital Counter; 201134091 314: LNA; 312: DSP; 316: mixer; 318: PA; 325: integrated circuit; 400: RF receiver front-end circuit; 500: RF transmitter front-end circuit.
；S 15;S 15